Utility meters are devices that, among other things, measure the consumption of a utility generated commodity, such as electric energy, gas, or water, by a residence, factory, commercial establishment or other such facility. Utility service providers employ utility meters to track customer usage of utility generated commodities. Utilities track customer usage for many purposes, including billing and tracking demand for the relevant consumed commodity.
Increasingly, meters employ electronic circuits to both reduce the number of moving parts in the meters and to provide enhanced metering and data collection services. The use of electronic circuits is most prevalent in utility meters that measure electricity consumption, also known as electricity meters. However, electronic circuits may be implemented in gas or water meters as well.
In addition, meters have increasingly employed communication circuits to facilitate remote meter reading. Specifically, a utility meter is typically installed at or near the facility or residence of each customer. Service providers historically have used field technicians or “meter-readers” to obtain usage data from the remotely located utility meters. Manual meter reading, however, imposes significant labor costs and is vulnerable to transportation problems and human error. Consequently, utility meters have been increasingly outfitted with communication circuits to facilitate remote meter reading.
The inclusion of communication circuits can have negative consequences, particularly in electronic meters. One issue that is always present is the need for accuracy in meters. Industry and/or government standards require metering accuracy as a protection to the consumer, among other things. Communication circuits can reduce the accuracy of meter measurements, particularly when using electronic measurement circuits.
For example, meter communication circuits can sometimes employ high frequency fixed and spread spectrum wireless devices that operate in the frequency range of on the order of 100 MHz to 1 GHz. Such high frequency signals may radiate back onto analog measurement lines within the meter, introducing a high frequency signal on the power line signal to be measured. This induced high frequency signal can reduce meter accuracy.
A further issue related to meters having communication circuit arises from the fact that the same meter platform may be coupled with any of a plurality of compatible communication devices. In particular, it is desirable that meters may ideally be coupled with different communication circuits so that they may be made compatible with the various types of communication networks employed by utilities. Because of the interchangeability of communication circuits, any attempt to overcome the difficulties posed by one communication scheme may introduce unnecessary cost and/or possibly new difficulties with respect to other communication schemes.
There is a need, therefore, for an arrangement that reduces the probability of metering inaccuracies due to spurious signals caused by communication circuits in or around metering devices.